Example Exercise: 7.27 (Advanced High School Statistics & OpenIntro Statistics)

Slides are available at:

Chicken farming is a multi-billion dollar industry, and any methods that increase the growth rate of young chicks can reduce consumer costs while increasing company profits, possibly by millions of dollars. An experiment was conducted to measure and compare the effectiveness of various feed supplements on the growth rate of chickens. Newly hatched chicks were randomly allocated into six groups, and each group was given a different feed supplement.

(a) Describe the distributions of weights of chickens that were fed linseed and horsebean.
(b) Do these data provide strong evidence that the average weights of chickens that were fed linseed and horsebean are different? Use a 5% significance level.
(c) What type of error might we have committed? Explain.
(d) Would your conclusion change if we used α = 0.01?

All of our textbooks are free to download: